project CHANDRAYAAN-2 spectrometer for IIRS

Chandrayaan-2 is a lunar space probe, the second of its name. Its launch is programmed by ISRO, the Indian space agency, for july 2019.
It includes an orbiter equipped with observation instruments, a landing gear that must land on the moon’s surface near the South Pole and land a rover.

AMOS collaborated with ISRO in the development of the infrared imaging spectrometer of the orbiter (IIRS instrument), designed in particular to characterize the abundance of water or hydroxyl ions in the lunar surface.

The qualification (QM) and flight (FM1) models of the optics of this hyperspectral instrument were manufactured by AMOS. They were recently accepted and delivered to ISRO’s Space Application Center in India.

IIRS instrument (test configuration)

IIRS in FOCAL 3 at CSL (Liège)

The Chandrayaan-2 mission is a strategic mission for India as it will be the first time they plan a controlled lunar landing to move along a small rover and only the second time they design a lunar mission.

The hyperspectral instrument consists of 6 mirrors, a slot and a diffraction grating.
Regarding the latter, this is a first for AMOS with an innovative design involving a convex shape and multiple blaze angles to obtain a good diffraction efficiency over an extended spectral range (0.8 microns to 5 microns).

AMOS also tested (in ground configuration) the performance of the complete vacuum instrument at 240 Kelvins temperature at the CSL with a dedicated infrared detector.
These tests have demonstrated the excellent performance of the instrument.